1. Field of Invention
The present invention relates to machinery with power fluid systems. More specifically, this invention is a device which would be used in conjunction with construction, agricultural, portable power or other machinery of cycling operations, for instance with a frontal loader, whose main distinguishing feature is a big change of the volume of developed engine power in the process of the working cycle. In this condition the energy recuperation provides minimum fuel consumption and environment—friendly machine.
2. Background of the Invention
The widespread machinery power fluid systems is used to drive working equipment of widely known machinery—mountainous, construction, agricultural, transportation automotive and other heavy equipment.
Power fluid systems are known to consist basically of familiar, expected and obvious structural configurations, notwithstanding a lot of designs encompassed by the crowded prior art which have been developed for the fulfillment of countless objectives and requirements.
By way of example, U.S. Pat. No. 4,779,416 to Chatterjea (1988), U.S. Pat. No. 4,962,825 to Albright at al. (1990), U.S. Pat. No. 5,083,428 to Kubomoto (1992), U.S. Pat. No. 6,170,261 to Ishizaki et al.(2001). U.S. Pat. No. 6,434,864 to the same inventor Epshteyn (2002)
While these devices fulfill their respective, particular objective and requirements, the aforementioned patents do not describe compact hydrostatic energy recuperation system and method of operation for providing increased efficiency and specific power with the minimal installation space, weight and cost.
The machinery with working equipment and energy recuperation system in widespread use suffer from the following known disadvantages:                (a) The machinery working equipment pump charges the pneumohydraulic accumulator (PHA) during the lowering process and whole oil volume goes directly from the working equipment cylinders to the PHA. This requires the PHA volume in several times greater than volume of the working equipment cylinders and decreases the energy recuperation system effectiveness. The PHA has large weight, cost and installation space.        (b) The energy recuperation system during the working equipment lifting defines pump operation in the hydraulic motor mode. This hydraulic motor operates in the pump mode during the working equipment lowering process and requires increased suction oil pressure magnitude. The whole oil volume goes directly from a working equipment cylinders to the PHA during the lowering process impede to provide this requirement.        (c) The working equipment lowering process occurs with large volume oil goes from the tank via pump and cylinders to the PHA charge. This defines the large oil volume change within the tank and requires a greater tank volume with large weight, cost and installation space. This not allows use the conventional machine hydraulic system tank for the energy recuperation system operation.        (d) The oil goes from the working equipment cylinders directly to the PHA has small pressure magnitude and large oil flow instead of use large pressure magnitude and small oil flow. This prevent from use the compact hydrostatic energy recuperation system.        
The mentioned disadvantages impede to realize compact and not expensive energy recuperation system, which has great potential to realize the environmentally—friendly machinery with minimum fuel consumption and volume of toxic exhaust.